Thermodynamics of binding 2,2 '-bipyridineglycinato palladium (II) chloride on human serum albumin

The interaction of human serum albumin (HSA) with 2,2'-bipyridineglycinato palladium (II) chloride was studied by isothermal titration microcalorimetr y at 27 degrees C and equilibrium dialysis and UV-Vis. spectrophotometry te chniques at temperatures of 27 & 37 degrees C in 2.5 mM phosphate buffer so lution at pH = 7.0. The enthalpy of binding was calculated from binding dat a, which were obtained from equilibrium dialysis in terms of the Wyman bind ing potential theory related to the van't Hoff relation. The enthalpy of HS A unfolding was determined by subtraction of the microcalorimetric enthalpy (binding and unfolding enthalpies) and the enthalpy of binding. The enthal py of HSA unfolding, due to the binding of that ligand, was 491.43 kJ mol(- 1).